Pyloric valve

ABSTRACT

A pyloric valve for regulating the flow of fluids in the pyloric region a patient&#39;s gastrointestinal tract is disclosed herein. In one embodiment, a pyloric valve includes a plurality of axially connected blocking members located along a longitudinal axis of the valve in a proximal to distal direction. Each blocking member of the valve preferably includes at least one blocking portion defining at least one entryway adapted to receive fluids such as chyme therethrough. The at least one entryway of each blocking member is preferably not aligned with the at least one entryway of each blocking member adjacent thereto along the longitudinal axis. The non-alignment of the at least one entryways of the blocking members preferably creates a non-linear path for fluids such as chyme to travel through the pyloric region of the patient.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of the filing dates of U.S.Provisional Patent Application No. 61/123,472 filed Apr. 9, 2008,entitled PYLORIC VALVE, the disclosure of which is hereby incorporatedherein by reference.

FIELD OF THE TECHNOLOGY

The present invention relates to a device implanted in thegastrointestinal tract to aid in controlling obesity, and moreparticularly relates to a pyloric valve implanted in the pyloric regionof the stomach to control the flow of chyme through the stomach.

BACKGROUND OF THE INVENTION

Obesity is a condition in which the natural energy reserve, stored inthe fatty tissue of humans and other mammals, is increased to a pointwhere it is associated with certain adverse health conditions. Althoughobesity is an individual clinical condition, it is increasingly viewedas a serious and growing public health problem. Excessive body weighthas been shown to predispose to various diseases, particularlycardiovascular diseases, diabetes mellitus type 2, sleep apnea andosteoarthritis.

The main treatment for obesity is to reduce body fat by eating fewercalories and increasing exercise. A beneficial side effect of exerciseis to increase muscle, tendon, and ligament strength, which helps toprevent injury from accidents and vigorous activity. Diet and exerciseprograms produce an average weight loss of approximately 8% of totalbody mass (excluding program drop-outs). Not all dieters are satisfiedwith these results, but a loss of as little as 5% of body mass cancreate large health benefits. Much more difficult than reducing body fatis keeping it off. Eighty to ninety-five percent of those who lose 10%or more of their body mass by dieting regain all that weight back withintwo to five years.

The body has systems that maintain its homeostasis at certain setpoints, including body weight. Therefore, keeping weight off generallyrequires making exercise and healthy eating a permanent part of aperson's lifestyle. Certain nutrients or chemicals, such asphenylalanine, are natural appetite suppressants which allow resettingof the body's set point for body weight. However, diet, and exerciseand/or appetite suppressants may not result in sufficient weight lossfor patients with serious medical conditions.

An alternative mechanism for hunger suppression is to decrease the rateof gastric emptying without the use of ingesting chemicals. In effect,obesity can be controlled by implanting a device in the gastrointestinaltract that may regulate satiety. It should be understood that theeffects of regulating satiety may vary between individuals.

Partially undigested food in the gastrointestinal track is generallyreferred to as chyme. A need exists for a device that is structured toinhibit the rate that chyme passes through the gastrointestinal trackwhile allowing natural peristaltic action to occur.

Satiety receptors are generally located all along the stomach. If chymeremains in the stomach for a longer period of time than it naturallywould before flowing into the small intestine, then the satietyreceptors have a greater chance of being activated to signal thesensation of being satiated. Thus, a device implanted in the stomachand/or small intestine may enhance the ability of an overweight or obesepatient to feel satiated so that the patient does not overeat, and infact eat less than normal.

SUMMARY OF THE INVENTION

A first aspect of the present invention is a pyloric valve. Inaccordance with one embodiment of this first aspect, the pyloric valveincludes a plurality of axially connected blocking members located alonga longitudinal axis of the valve in a proximal to distal direction.Preferably, each blocking member defines at least one entryway adaptedto receive chyme therethrough, wherein the at least one entryway definedby each blocking member is not aligned along the longitudinal axis withthe at least one entryway defined by each blocking member adjacentthereto.

A second aspect of the present invention is a pyloric valve. Inaccordance with one embodiment of this second aspect, the pyloric valvehas a proximal section including a plurality of axially connectedblocking members located along a longitudinal axis of the valve in aproximal to distal direction. Preferably, each blocking member definesat least one entryway adapted to receive chyme therethrough. Preferably,the at least one entryway defined by a first blocking member is notaligned with the at least one entryway defined by a second blockingmember located adjacent to the first blocking member in the distaldirection along the longitudinal axis such that chyme passing throughthe at least one entryway defined by the first blocking member cannottravel in a linear path through the at least one entryway defined by thesecond blocking member. The pyloric valve preferably further includes adistal section connected to the proximal section distally along thelongitudinal axis, the distal section including an elongate sleeveadapted for the passage of the chyme therein.

A third aspect of the present invention is a pyloric valve. Inaccordance with one embodiment of this third aspect, the pyloric valvehas an inlet formed at a proximal end of the pyloric valve. Preferably,the inlet has at least one entryway adapted to receive chymetherethrough. Preferably, the pyloric valve further includes at leastone blocking member located distal to the entryway of the inlet, theblocking member adapted to receive chyme having flowed through the atleast one entryway of the inlet thereon. Preferably, the at least oneblocking member has at least one entryway misaligned with the at leastone entryway of the inlet, wherein the chyme passing through the atleast one entryway of the inlet cannot travel in a linear path throughthe at least one entryway of the blocking member. Preferably, thepyloric valve further includes an elongate sleeve located distal to theat least one blocking member, the elongate sleeve adapted for thepassage of chyme therein.

In accordance with one embodiment of this third aspect of the presentinvention, the inlet includes at least one blocking portion having afirst side surface, a second side surface, and a proximal surface,wherein the proximal surface is adapted to receive chyme thereon.

In accordance with another embodiment of this third aspect of thepresent invention, the at least one entryway is formed between the firstside surface and the second side surface of the at least one blockingportion. Preferably, the at least one entryway is approximately 1-2 mmin width.

In accordance with yet another embodiment of this third aspect of thepresent invention, an entryway is formed between adjacent first andsecond side surfaces of adjacent blocking portions. Preferably, the atleast one entryway is approximately 1-2 mm in width.

In accordance with still yet another embodiment of this third aspect ofthe present invention, the at least one blocking member includes a firstside surface, a second side surface, and a proximal surface, wherein theproximal surface is adapted to receive the chyme thereon.

In accordance with still yet another embodiment of this third aspect ofthe present invention, the pyloric valve of the present inventionfurther includes a plurality of blocking members distal to the inlet,wherein each successive blocking member is located distal to theblocking member that precedes it. Preferably, the plurality of blockingmembers each include a first side surface, a second side surface, and aproximal surface, wherein the proximal surface is adapted to receive thechyme thereon.

In accordance with still yet another embodiment of this third aspect ofthe present invention, the inlet includes a plurality of entryways.

In accordance with still yet another embodiment of this third aspect ofthe present invention, the pyloric valve of the present inventionfurther includes pyloric columns connecting a distal end of the at leastblocking member and a proximal end of the sleeve. Preferably, the sleeveincludes at least one aperture therethrough, the at least one apertureadapted to receive fluid such as bile or other gastric secretionstherein. Preferably, the sleeve further includes a radiopaque markerlocated on a surface of the sleeve or embedded throughout the device.

A fourth aspect of the present invention includes a method of regulatingthe flow of chyme through a stomach of a patient. Preferably, the stepsof the method include implanting a pyloric valve into the pyloric regionbetween a stomach and small intestines of the patient. Preferably, thepyloric valve includes an inlet formed at a proximal end of the pyloricvalve, the inlet having at least one entryway adapted to receive chymetherethrough. Preferably, the pyloric valve further includes at leastone blocking member located distal to the entryway of the inlet, theblocking member adapted to receive chyme having flowed through and/oraround the at least one entryway of the inlet thereon. Preferably, theat least one blocking member has at least one entryway misaligned withthe at least one entryway of the inlet, wherein the chyme passingthrough and/or around the at least one entryway of the inlet cannottravel in a linear path through the at least one entryway of theblocking member. Preferably, the pyloric valve further includes anelongate sleeve located distal to the at least one blocking member, theelongate sleeve adapted for the passage of chyme therein. Preferably thepyloric valve further includes a plurality of pyloric columns connectinga distal end of the at least blocking member and a proximal end of thesleeve, the plurality of pyloric columns being compliant such that thenatural peristaltic action of the pyloric sphincter is not inhibited bythe plurality of the pyloric columns. Preferably, the pyloric valve isimplanted such that the inlet is located adjacent the pyloric antrum ofthe stomach, the at least one blocking member is located proximal to thepyloric sphincter, the plurality of the pyloric columns are locatedadjacent the pyloric sphincter, and the sleeve is located distal to thepyloric sphincter, the sleeve beginning in the duodenum and terminatingin the small intestines.

A fifth aspect of the present invention includes a method of regulatingthe flow of chyme through a stomach of a patient. Preferably, the stepsof the method include placing an endoscopic delivery tool into a stomachof a patient; passing a pyloric valve through the endoscopic deliverytool; and implanting the pyloric valve in the pyloric region of thestomach. Preferably, the pyloric valve includes an inlet having at leastone entryway formed therein; at least one blocking member located distalto the entryway of the inlet; a duodenal ring adapted to maintain theposition of a portion of the valve adjacent to the pyloric sphincter;and a sleeve, wherein at least a portion of the sleeve is located distalto the duodenal ring such that chyme passing through the stomach isallowed to come in contact with the inlet and blocking members beforeflowing through the sleeve.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete appreciation of the subject matter of the presentinvention and the various advantages thereof can be realized byreference to the following detailed description in which reference ismade to the accompanying drawings in which:

FIG. 1 is a view of a portion of a normal gastrointestinal tract of ahuman.

FIG. 2 is a perspective view of a pyloric valve of the presentinvention.

FIG. 3 is a side elevational view of the pyloric valve of FIG. 2 showingthe presence of a plurality of bile holes along a sleeve of the pyloricvalve.

FIG. 4 is a an alternative side elevational view of the pyloric valve ofFIG. 2, wherein the pyloric valve is shown rotated approximately 90degrees from the orientation it is shown in FIG. 3.

FIG. 5 is a top plan view of the pyloric valve of FIG. 2, showing afirst blocking member or inlet of the pyloric valve including aplurality of spaced portions that chyme may pass through and/or aroundas the chyme enters from the stomach and through and/or around thepyloric valve.

FIG. 6 is a view of the pyloric valve of FIG. 2 implanted along theportion of the gastrointestinal tract shown in FIG. 1.

FIG. 7 is a view of another embodiment of a pyloric valve in accordancewith the present invention shown implanted along the portion of thegastrointestinal tract shown in FIG. 1.

FIG. 8 is a view of another embodiment of a pyloric valve in accordancewith the present invention shown having a duodenal ring structured toaid in anchoring the pyloric valve in the duodenum.

FIG. 9 is a view of another embodiment of a pyloric valve in accordancewith the present invention having a shorter sleeve than the pyloricvalve shown in FIG. 8.

FIG. 10 is another embodiment of a pyloric valve in accordance with thepresent invention having a plurality of blocking members with noentryways.

FIG. 11 is a view of another embodiment of a pyloric valve in accordancewith the present invention having a shorter sleeve than the pyloricvalve shown in FIG. 10.

DETAILED DESCRIPTION

As used herein, when referring to parts of the body, the term “proximal”means closer to the heart and the term “distal” means more distant fromthe heart. The term “inferior” means lower or bottom and the term“superior” means upper or top. The term “anterior” means towards thefront part of the body or the face and the term “posterior” meanstowards the back of the body. The term “medial” means toward the midlineof the body and the term “lateral” means away from the midline of thebody.

Referring to the drawings, wherein like reference numerals refer to likeelements, there is shown in FIG. 1 an example of a portion of agastrointestinal tract 10 of a human body. Two smooth muscle valves, orsphincters, contain the contents of the stomach within the stomach uponingestion. They are the esophageal sphincter (not shown) found in thecardiac region above the antrum cardiacum, and the pyloric sphincter 20shown dividing the stomach 30 from the small intestine 40. Pyloricsphincter 20 is a strong ring of smooth muscle at the end of the pyloriccanal functioning to help regulate the passage of chyme from stomach 30to the duodenum 50. Partially undigested food in the gastrointestinaltrack is generally referred to as chyme. Preferably, pyloric sphincter20 controls the flow of chyme therethrough by way of natural peristalticaction causing sphincter 20 to alternate between a relaxed state and acontracted state. As shown in FIG. 1, the pyloric antrum 60 is locatedbetween stomach 30 and pyloric sphincter 20 or it can be said thatpyloric antrum 60 is located proximally to pyloric sphincter 20.Therefore, duodenum 50 is located distally to pyloric sphincter 20.

Humans generally have satiety receptors 80 located all along the insidelining of stomach tissue as shown in FIG. 1. If chyme remains in theregion of the stomach before flowing into the small intestine, thensatiety receptors 80 have a greater chance of being activated, whichenhances the ability of an overweight or obese patient to feel satiatedsuch that they may have a reduction in their desire to eat.

Referring to FIGS. 2-5, an embodiment of the pyloric valve of thepresent invention is designated generally by reference numeral 100.Preferably, pyloric valve 100 is made of silicone or any otherbiocompatible polymeric material. Pyloric valve 100 is preferably apolymeric structure that is compliant and generally bendable whilehaving sufficient strength properties to prevent unintended deformationthereof. Some portions of pyloric valve 100 may be thicker for enhancedstrength properties. Preferably, if a portion of pyloric valve 10 isbent or twisted, the polymeric structure of the device allows it tochange back to an initial shape or configuration.

Pyloric valve 100 is structured to inhibit the rate that chyme passesthrough gastrointestinal track 10 thereby reducing the rate of gastricemptying thereby enhancing the ability of chyme to activate satietyreceptors 80 and in effect enhance satiety in a patient. Pyloric valve100 is also structured to inhibit malabsorption, which is generallyreferred to as an abnormality where increased absorption of food occursalong the gastrointestinal tract.

Pyloric valve 100 may be delivered into stomach 30 of gastrointestinaltrack 10 through one of the methods disclosed in U.S. Provisional PatentApplication No. 61/206,048 incorporated by reference herein in itsentirety. Generally, an endoscope is placed through a patient's mouthand into the esophagus of a patient and through to the patient's stomach30. Preferably, pyloric valve 100 is configured to have a lesser orcollapsed diameter while contained within an endoscope and may beexpanded to conform around a portion of inner surface 32 of adjacentstomach tissue after having been implanted in stomach 30. The compliantnature of pyloric valve 100 allows at least a portion of valve 100 to becollapsed and later opened or expanded into its initial configuration.Valve 10 may be made of shape memory material to expand back into aninitial uncollapsed configuration.

If pyloric valve 100 is delivered to the pyloric region of stomach 30 ina collapsed state or position, valve 100 is preferably first expandedbefore the endoscope or endoscopic delivery tool is removed. Additionalinstruments (not shown) may be delivered to the region of stomach 30 inwhich pyloric valve 100 is implanted and used to expand and/or deliverthe first blocking member or inlet 102 of valve 100. Preferably, inlet102 is the first part of valve 100 chyme comes in contact with whiletraveling through gastrointestinal tract 10 and preferably has thelargest diameter of all features included in pyloric valve 100.

Before the endoscope is removed from inside stomach 30 of a patient,inlet 102 is first placed in a preferable position in a pyloric regionlocated just proximally of pyloric antrum 60 and a distal portion ofvalve 100 is located in at least the duodenum 50 and preferably islocated in the small intestines 40. Inlet 102 may be set in the generallocation of the pyloric antrum 60 or even distal of pyloric antrum 60.While inlet 102 of valve may be set in a plurality of positions in thepyloric region, inlet 102 is preferably placed proximally of pyloricsphincter 20.

Pyloric valve 100 preferably includes a proximal end 104 and a distalend 106. As shown in FIGS. 3 and 4, located between proximal end 104 anddistal end 106 of valve 100 from a proximal to distal direction are aplurality of axially connected blocking members or flanges preferablyincluding an inlet 102 and blocking members 112, pyloric columns 114,duodenal ring 116, and sleeve 110. Inlet 102 is generally located at theproximal end 104 of valve 100 while a terminal end or portion 108 ofsleeve 110 is generally located at the distal end 106 of valve 100.

Preferably, pyloric valve 100 includes a plurality of axially connectedblocking members 112 located along a longitudinal axis 115 of the valvein a proximal to distal direction. Preferably, each blocking member 112defines at least one entryway 148 adapted to receive chyme therethrough,wherein the at least one entryway 148 defined by each blocking member112 is not aligned along longitudinal axis 115 with an at least oneentryway 148 defined by each blocking member 112 located adjacentthereto.

During use, inlet 102 is the portion of pyloric valve 100 with thelargest diameter such that the most amount of chyme may come in contactwith the proximal end 104 of valve 100. First blocking member or inlet102 preferably includes a first row of spaced apart flanges or blockingportions 120. First blocking member 102 is generally disc shaped havinga plurality of entryways 128 forming the flange or blocking portions120. Flanges 120 having a thickness measured from a proximal to distalend thereof of approximately 1 mm to 10 mm. Flanges 120 may be bent by asurgeon during positioning in stomach 20 to aid in the insertion thereofor may bend or flex due to contact with surrounding stomach tissue asnatural peristaltic action of the stomach occurs.

Preferably, first blocking member 102 includes four blocking portions orflanges 120, but preferably includes at least one flange 120. In anembodiment wherein first blocking member 102 includes only one flange120 there is no entryway 128 in first blocking member 102. Each flange120 preferably has a proximal surface 122 adapted to receive chymethereon. Each flange 120 preferably further includes a first sidesurface 124 and a second side surface 126 representing the thickness ofeach flange 120 as mentioned above.

A first side surface 124 of a flange 120 is preferably 1-2 mm apart froma second side surface 126 of an adjacent flange 120 as shown in FIG. 5.First blocking member or inlet 102 defines at least one entryway 128formed by the separation in a first side surface 124 of a flange 120 anda second side surface 126 of an adjacent flange 120. Entryways 128 areadapted to receive chyme therethrough in order for the chyme to movedistally on to flanges 120 of additional blocking members 138 that arelocated distally along pyloric valve 100 or rather move distally tophalanges 114 or sleeve 110. While entryways 128 preferably have a widthof 1-2 mm, it is contemplated by the present invention that entrywaysmay have a width of 0.5-10 mm, or even less than 0.5 mm or even greaterthan 10 mm.

In the present invention, entryways 128 are preferably configured toreceive chyme therethrough. Chyme generally flows from the proximal todistal direction of pyloric valve 100 through entryways 128 and thenthrough pyloric columns 114 and sleeve 110. Chyme generally will contacta proximal surface 122 of a flange 120 before passing through and/oraround entryways 128. This is because there is so much more surface areaon proximal surfaces 122 for the chyme to contact than entryways 128 topass through and/or around. Some chyme may pass through entryways 128 ofinlet 102 without having contacted proximal surface 122 of flanges 120.In such instances, chyme passes around flanges 120 between flanges 120and surround skin tissue.

Prior to the chyme contacting the first blocking member or inlet 102 ofvalve 100, the consistency of the chyme generally allows for some of thechyme to build-up proximally of the proximal surfaces 122 of flanges 120such that satiety receptors 80 may become activated. The function offlanges 120 of inlet 102 is to inhibit the flow of chyme through and/oraround inlet 102 such that chyme may preferably pass only through and/oraround entryways 128 of inlet 102.

After chyme passes through and/or around entryways 128 of inlet 102, thechyme preferably flows towards blocking members 112 of valve 100.Blocking members 112 are configured to preferably rest against innersurface 32 of stomach tissue in pyloric antrum 60 proximally to pyloricsphincter 20. Blocking members 112 are preferably a plurality of evenlyspaced rows 138. Each row 138 of blocking members 112 is structured muchlike first blocking member or inlet 102. Blocking members 112 may belocated along the length of valve 100 between inlet 102 and pyloriccolumns 114 in a staggered manner. Each row 138 may include four flanges140, but each row 138 preferably includes at least one flange 140. In anembodiment wherein a row 138 includes only one flange 140 there is noentryway in row 138. Each flange 140 preferably has a proximal surface142 adapted to receive chyme thereon. Each flange 140 preferably furtherincludes a first side surface 144 and a second side surface 146representing the thickness of each flange 140. A first side surface 144of a flange 140 is preferably 1-2 mm apart from a second side surface146 of an adjacent flange 140 as shown generally in FIG. 5.

Each row 138 further includes at least one entryway 148 formed by theseparation in a first side surface 144 of a flange 140 and a second sidesurface 146 of an adjacent flange 140, entryway 148 adapted to receivechyme therein such that chyme passes onto another flange 140 locateddistal to entryway 148 or rather travels distally to pyloric columns114. While entryways 148 preferably have a width of 1-2 mm, it iscontemplated by the present invention that entryways may have a width of0.5-10 mm, or even less than 0.5 mm or even greater than 10 mm.

Entryways 148 are configured to receive chyme therethrough. Chymegenerally will contact a proximal surface 142 of a flange 140 of a row138 before passing through an entryway 148 or rather between a flange140 and surrounding skin tissue. Chyme may therefore contact a proximalsurface 142 of a flange 140 and then flow through an entryways 148 of arow 138 and onto a subsequent row 138 located distal to the row 138 thechyme flowed from.

As stated above, there are preferably four rows 138 of blocking members112. Each row 138 may include four flanges 140 of which each flangeincludes a median portion 150, wherein each median portion 150 of eachflange 140 of a respective row 138 is located 900 in a circumferentialdirection from an adjacent median portion 150. Located distally from afirst row 138 is a second row 138 of flanges 140, wherein the flanges140 of the second row 138 are preferably located 450 in acircumferential direction from the median portion 150 of the flanges 140of the first row 138. Located distally from the second row 138 is athird row 138 of flanges 140, wherein the flanges 140 of the third row138 are preferably located 450 in a circumferential direction from themedian portion 150 of the flanges 140 of the second row 138. Therefore,as chyme passes through an entryway 128 or 148, the chyme will generallyhit a flange 140 of a distally located row 138 before flowing through anentryway 148 of the distally located row 138 or between a flange 140 ofthe row 138 and the skin tissue surrounding the flange 140.

The chyme may then continue to move in a distal direction through valve100 wherein the chyme will flow off of a flange 140 of a row 138 andonto a flange 140 of a subsequent row 138 impeding the flow of the chymethrough blocking members 112 of valve 100. The flanges and entryways ofrows are preferably misaligned in the manner described above but may bemisaligned in a different manner such that median portions 150 offlanges 140 are located 300 to 600 in a circumferential direction froman adjacent median portion located distally or proximally to it.

Located distal to blocking members 112 are pyloric columns 114.Preferably, valve 100 includes four pyloric columns 114, but it iscontemplated by the present invention that valve 100 includes at leasttwo pyloric columns 114. Valve 100 is implanted in the pyloric regionsuch that pyloric columns 114 are located adjacent pyloric sphincter 20.Pyloric columns 114 are preferably compliant and flexible such that thenatural peristaltic action of pyloric sphincter is not impeded. Pyloriccolumns 114 are preferably separated such that chyme passing fromblocking members 112 may pass through a separation in pyloric columns114 and into sleeve 110.

Valve 100 is implanted in the pyloric region such that sleeve 110 islocated just distal to pyloric sphincter 20. Sleeve 110 may have anelongate length such that sleeve 110 passes through duodenum 50 and intosmall intestines 40 as shown in FIG. 6 or rather may have a terminalportion 108 terminating in duodenum 50 such that it is not located insmall intestines 50 as shown in FIG. 7.

As chyme passes through duodenal ring 116 from pyloric columns 114, thechyme preferably flows into sleeve 110 of valve 100. Depending on aparticular patient, sleeve 110 of valve 100 may be 0.5 inches to 24inches long. Preferably, duodenal ring 116 is located near a proximalend of sleeve 110 and preferably acts as a fixation portion for sleeve110. Duodenal ring 116 generally is configured to help maintain theposition of sleeve 110 in a position located just distal to pyloricsphincter 20.

In one embodiment, a fixation portion of sleeve 110 may be a taperedportion that has a slightly greater thickness than the rest of sleeve110. This greater thickness preferably allows the fixation portion ofsleeve 110 to engage surrounding inside tissue of the duodenum or smallintestine, thereby inhibiting movement of the fixation portion withinthe duodenum or small intestine.

A function of sleeve 110 in valve 100 is to aid in inhibitingmalabsorption in the duodenum and/or small intestines. As mentionedabove, malabsorption is generally known as a state arising fromabnormality in digestion or absorption of food nutrients across thegastrointestinal tract. Sleeve 110 acts as a passage for chyme to flowthrough, wherein when the chyme passes through the sleeve, the chyme maynot contact the tissue lining on the inside of the duodenum and/or smallintestine and therefore cannot be absorbed into and/or through thelining on the duodenum and/or small intestine.

Preferably, sleeve 110 of valve 100 further includes at least oneaperture 180 configured to receive bile secreted from the pancreastherein. Bile of the pancreas generally is used to aid in the digestionprocess. Therefore, at least one aperture 180 in sleeve 110 allows bileto enter sleeve 110 and aid in digesting the chyme flowing throughsleeve 110.

The distal or terminal portion 108 of sleeve 110 may include aradiopaque marker 190 therein. The radiopaque marker 190 may be anitinol insert that functions to show up on an X-ray so that a surgeonmay locate the distal end 106 of valve 100 within gastrointestinal track10. Radiopaque marker 190 may alternatively be a bead located withinsleeve 110 or on outside surface 111 of sleeve 110. Alternatively, aradiopaque silicone-barium mixture may be used to manufacture thedevice. Preferably, sleeve 110 has a constant diameter throughout itslength.

In another embodiment, an inlet 202 of a valve 200 is configured toreceive chyme therein. Inlet 202 preferably includes a compliantcircular frame 204 or ring that may be collapsed in order to passthrough endoscope 90, wherein compliant ring 204 may thereafter expandto conform to tissue on inside surface 32 of stomach 30. While compliantring 204 of inlet 202 is configured to engage inside surface 32 ofstomach 30, it is not configured to over-distend the stomach wall.Preferably, inlet 202 acts as a funnel to receive chyme therein beforepassing through to phalanges 222 of valve 200. Inlet 202 preferablyincludes a plurality of entryways 228 therein which serve to allow chymeto pass therethrough but also includes a plurality of spaced apartflanges 220 which form entryways 228 that serve to inhibit the rate ofpassage of chyme therethrough and/or around.

As chyme passes through and/or around entryways 228 in inlet 202, thechyme will contact a staggered flange 240 of phalanges 222. Preferably,phalanges 222 include a plurality of rows 238 of staggered flanges 240.

FIG. 8 shows another embodiment of a pyloric valve in accordance withthe present invention. Pyloric valve 300 includes a duodenal ring 316having a larger circumference. Duodenal ring 316 is preferablyconfigured to aid in anchoring pyloric valve 300 in the pyloric regionwhile still allowing the natural peristaltic action of the pyloricsphincter to occur. As described above, after pyloric valve 300 isimplanted in the pyloric region, duodenal ring 316 is preferably locateddistal to the pyloric sphincter in the duodenum. Preferably, thecircumference of duodenal ring 316 closely matches that of thesurrounding tissue. It should be understood that duodenal ring 316 mayhave a diameter that is slightly larger than the surrounding tissue suchthat the surrounding tissue may slightly stretch while duodenal ring 316is anchored in the duodenum.

Preferably, sleeve 310 may include a plurality of slits 320 therethroughconfigured to receive bile secreted from the pancreas therein.Therefore, at least one slit 320 in sleeve 310 allows bile to entersleeve 310 and aid in digesting the chyme flowing through sleeve 310.

In FIG. 9, pyloric valve 300′ includes a shorter sleeve 310′. Sleeve310′ may still be positioned inside the small intestines after pyloricvalve 300′ is implanted in the pyloric region. As described above, afunction of sleeve 310′ is to aid in inhibiting malabsorption in theduodenum and/or small intestines. Preferably, sleeve 310′ acts as apassage for chyme to flow through. Here, sleeve 310′ is shorter, andchyme will come in contact with tissue of the small intestine fasterthan it would if pyloric valve 300 having a longer sleeve 310 wasinstead implanted in the pyloric region.

FIG. 10 shows another embodiment of a pyloric valve in accordance withthe present invention. Pyloric valve 400 has no entryways in inlet 402or blocking members 412. In this embodiment, all the chyme passingthrough pyloric valve 400 will have to pass around inlet 402 andblocking members 412 between the perimeter of inlet 402 and blockingmembers 412 and the surrounding tissue. The chyme that passes aroundinlet 402 and blocking members 412 will eventually travel around and/orthrough the pyloric columns 414, duodenal ring 416 and sleeve 410 ofpyloric valve 400.

In FIG. 11, pyloric valve 400′ includes a shorter sleeve 410′. Sleeve410′ may still be positioned inside the small intestines after pyloricvalve 400′ is implanted in the pyloric region. As described above, afunction of sleeve 410′ is to aid in inhibiting malabsorption in theduodenum and/or small intestines. Preferably, sleeve 410′ acts as apassage for chyme to flow through. Here, sleeve 410′ is shorter, andchyme will come in contact with tissue of the small intestine fasterthan it would if pyloric valve 400 having a longer sleeve 410 wasinstead implanted in the pyloric region.

Although the invention herein has been described with reference toparticular embodiments, it is to be understood that these embodimentsare merely illustrative of the principles and applications of thepresent invention. It is therefore to be understood that numerousmodifications may be made to the illustrative embodiments and that otherarrangements may be devised without departing from the spirit and scopeof the present invention as defined by the appended claims.

1. A pyloric valve comprising: a plurality of axially connected blockingmembers located along a longitudinal axis of the valve in a proximal todistal direction, wherein each blocking member defines at least oneentryway adapted to receive chyme therethrough, wherein the at least oneentryway defined by each blocking member is not aligned along thelongitudinal axis with the at least one entryway defined by eachblocking member adjacent thereto.
 2. The pyloric valve of claim 1,wherein the plurality of axially connected blocking members eachincludes a first side surface, a second side surface, and a proximalsurface, wherein the proximal surface is adapted to receive the chymethereon.
 3. A pyloric valve comprising: a proximal section including aplurality of axially connected blocking members located along alongitudinal axis of the valve in a proximal to distal direction, eachblocking member defining at least one entryway adapted to receive chymetherethrough, wherein the at least one entryway defined by a firstblocking member is not aligned with the at least one entryway defined bya second blocking member located adjacent to the first blocking memberin the distal direction along the longitudinal axis such that chymepassing through the at least one entryway defined by the first blockingmember cannot travel in a linear path through the at least one entrywaydefined by the second blocking member; and a distal section connected tothe proximal section distally along the longitudinal axis, the distalsection including an elongate sleeve adapted for the passage of thechyme therein.
 4. The pyloric valve of claim 3, wherein each of theplurality of blocking members includes at least one blocking portionhaving a first side surface, a second side surface, and a proximalsurface, wherein the proximal surface is adapted to receive chymethereon.
 5. The pyloric valve of claim 4, wherein the at least oneentryways are formed between the first side surface and the second sidesurface of the at least one blocking portion.
 6. The pyloric valve ofclaim 4, wherein an at least one entryway is formed between adjacentfirst and second side surfaces of adjacent blocking portions.
 7. Thepyloric valve of claim 6, wherein the at least one entryway isapproximately 1-2 mm in width.
 8. The pyloric valve of claim 3, furthercomprising an intermediate section having a plurality of spaced columnsconnecting the proximal section to the distal section.
 9. The pyloricvalve of claim 3, wherein the elongate sleeve includes at least oneaperture therethrough, the at least one aperture adapted to receivefluid such as bile or other gastric secretions therein.
 10. The pyloricvalve of claim 3, wherein the sleeve includes a radiopaque markerlocated on a surface of the sleeve.
 11. A method of regulating the flowof chyme through a stomach of a patient, comprising: implanting apyloric valve into the pyloric region between a stomach and smallintestines of the patient, the pyloric valve comprising: an inlet formedat a proximal end of the pyloric valve, the inlet having at least oneentryway adapted to receive chyme therethrough; and at least oneblocking member located distal to the at least one entryway of theinlet, the blocking member adapted to receive chyme having flowedthrough the at least one entryway of the inlet thereon, the at least oneblocking member having at least one entryway not aligned with the atleast one entryway of the inlet, wherein the chyme passing through theat least one entryway of the inlet cannot travel in a linear paththrough the at least one entryway of the blocking member.
 12. The methodof claim 11, wherein the pyloric valve further comprises an elongatesleeve located distal to the at least one blocking member, the elongatesleeve adapted for the passage of chyme therein.